This invention relates to an apparatus for operating an externally ignited, mixture-compressing internal combustion engine wherein the ignition is delayed as a function of signals emitted by a knocking sensor.
It is known to decrease the tendency of knocking in an externally ignited, mixture-compressing internal combustion engine by altering the moment of ignition. In this manner, the mixture compression in the internal combustion engine can be increased particularly in order to achieve a better degree of efficiency in the partial load range and to thus achieve a better fuel consumption. The tendency of knocking which appears during full load and high rpm's is reduced by a corresponding shift in the moment of ignition. Since knocking appears dependent upon the available fuel under different values of final mixture compression, it is conceivable that a circumstance sets in when despite a substantial shift of the ignition angle in the delaying sense, knocking is still not eliminated. Such an occurrence can lead to a damage to the internal combustion engine.